Reproduction lens system

ABSTRACT

A reproduction objective formed of five optical components separated by airspaces. The optical component placed next to the image plane is a positive meniscus. The second is a negative meniscus composed of two cemented elements. Both the first and second components represent the front portion of the objective which is separated by a large airspace, in which a mechanical diaphragm is located, from the rear portion of the objective. The rear portion consists of three menisci, the two extreme ones of which have a negative refractivity and the middle one of which has a positive refractivity. The design parameters comply with the following conditions: (1) FC &gt; fE &gt; fD (2) 5 fD &gt; fC &gt; 4 fD (3) d1 &gt; d6 &gt; d3 (4) M4 &gt; M3 &gt; OR = M1 (5) R10 &gt; R6 &gt; R5 (6) R11 &gt; R3 &gt; R7 where: FA, fB, fC, fD, fE are the focal lengths of individual optical components taken from the direction of the image plane, A, B, C, D, E; d1, d3, d6 are the axial thicknesses of corresponding elements; M1, M3, M4 ARE THE AXIAL AIRSPACES BETWEEN CORRESPONDING OPTICAL COMPONENTS, AND R3, R5, R6, R7, R10, R11 are the radii of curvature of the corresponding refracting surfaces.

[4 1 Aug. 12, 1975 United States Patent,

Paukert et a1.

REPRODUCTION LENS SYSTEM ponents separated by airspaces. The opticalcomponent placed next to the image plane is a positive me- Inventors:Miloslav Paukert; Libuse niscus. The second isa negative meniscuscomposed of two cemented elements. Both the first and second componentsrepresentthe front portion of the objec- Schwarzova, both of Prerov,Czechoslovakia 1 Assigneei p nalodni Podllik, PferOV, tive which isseparated by a large airspace, in which a Czechoslovakia mechanicaldiaphragm is located, from the rear por- [22} Filed Jan 21 1974 tion ofthe objective. The rear portion consists of Appl. No.: 434,943

three menisci, the two extreme ones of which have a negativerefractivity and the middle one of which has a positive refractivity.The design parameters comply Foreign Application Priority Data Febv 28,1973 Czechoslovakia (4) m m 2 m R R R Field of Search.....................t..... 350/215, 216 RU 3 R7V where:

References Cited" UNITED STATES PATENTS f,,, f f f f,; are the focallengths of individual 2,677,989 Tronnier.........................

Ak1in..........

2,807,983 Tronnier..........,.............,...v 350/215 elements;

m m are the axial airspaces between corresponding optical components,and R R R R R R are the radii of curvature of Primary Examiner.lohn K.Corbin Attorney, Agent, or FirmMurray Schaffer the corr ondin f act' rf'[57] ABSTRAC esp g re r mg su aces A reproduction objective formed offive optical com- 4 Claims, lzDrawing Figure dat\ 4 2 P I d 1 p I m PREPRQDUCTION LENS SYSTEM BACKGROUND OF THE INVENTION The inventionrelates to an optieal lens system and in particular to a reproductionobjective for negative enlargement.

It has been known to provide reproduction objectives having variousoptical lens systems, in which the required image magnification and theoptical length of the objective are generally determined by the distanceof the conjugated planes of micro-image or negative from the imageplane. In these arrangements the state of correction is usually quitesufficient to provide a speed around f/5.6 and a field of view of about42. However, the light distribution in the image plane with suchsystems, in respect to the particular requirements on the givenmicroimage reproduction, is usually unsuitable. Further, geometricvignetting of these objectives is around 40 percent, which is arelatively high value for reproduction purposes. When a more usefullight distribution in the image plane is required, objectives of a morecomplicated optical design, including special optical glasses must beused. This means that the objectives become too expensive.

It is the object of the present invention to provide a reproductionobjective that would offer perfect image quality defined by a greatresolving power together with a good contrast and contour sharpnessrendition and in which the image distortion is practically removed.

!t is a further object of the present invention to provide areproduction objective lens system in which geometric vignetting isreduced to a zero value for a relative aperture 174.5 and in which theobjective is of a simple optical design employing ordinary opticalglasses.

It is another object of this invention to provide an objective lenssystem having amagnification range of 7.5.r 3().\' which permits, on thebasis'of the parameters of the fundamental objectivefor a predetermineddistance of the conjugated planes of microimage from the image plane,the calculation of the parameters of another objective with such a focallength which would correspond tothe required image magnification. V

These objects'and other advantages of the present invention will be seenfrom the foregoing disclosure of the present invention.

I SUMMARY 0F INVENTION According to the present invention a' lens systemfor reproduction and enlargement is provided comprising v fivecomponents, the design parameters of which are chosen in such a mannerthat, the absolutevalue of the focal length of thc fifth component isless than the 2 which have a negative rcfractivity While the middle oneof which has a positive:refractivity. The space between the front andrear portions..i,e. between thc'sccond and third components is quitelargeand is provided with a mechanical diaphragm or iris. v

According to-the present invention the axial thickness ofthefifthcomponentisgreater than the axial thickness of the negativ'egmeniscus ofthe, second component, however itis less thanthe axialthickness of thefirst component. The airspace between.the third and the fourth componentequal or greater than the airspace between the' first'and the secondcomponent, however it'is less than the airspace between the fourth andthe fifth component. The radius of curvature ofthe sixthrefractingsurface is greater than the radius of curvature'of the fifthrefracting surface, however it is less than the radiusofcurvature'of'the tenth refracting surface. The radius of curvature ofthe third refracting surface is greater than the radius of curvature ofthe seventh refracting surface, howeverit is less than the radius ofcurvature of the eleventh refracting surface.

Full details of the present invention are given in the followingdescription and are illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS DESCRIRTION OF INVENTION As seen in theFIGURE the lens system comprises an arrangement of five separate lensesAB, C, D and E arranged along an optical axis 0. The component A isplaced next to the image plane Pand has; a form of a positive meniscuslens. The second component B is composed ofa positive meniscus lens Band a negative meniscus B which are cemented together in conventionalmanner. The third component C is a negative meniscus lens while thesucceeding fourth component D is a positive meniscus lens. The fifthcomponent E is placed next to the microimage or negative plane N in theform ofa negative meniscus lens. A mechanical diaphragm V or iris isplaced between the second component B and the third component C. Theradii of curvature of the individual refracting surfaces of therespective elements are labelled R, through R the axial thicknesses ofindividual elements are labelled (I. through (1,; and the axialairspaces between therespective components are labelled m through "1 Thelens components are axially spaced along a common optical axis and maybe arranged in a tube or similar housing of conventional design. Themechanical diaphragm may be any one of the conventional and well knowntype, currently available in this field.

In accordance with the present invention the lenses are arranged andtheir structure, focal lengths. radii, spacial dimensions and parametersare formed to have the following relationships:

(3) I, d (1;; (4) 121 m 2 m, (5) io R5 (6) where f', .ji1.j}.jib];- arethe focal lengths of individual optical components A. B. C. D. E: 1!d;-,. d are the axial thicknesses of corresponding elements; 111,. m 111are the axial airspaces between corresponding optical components and RR;,. R... R Rm. R are the radii of curvature of corresponding refractingsurfaces.

As a result of following the above relationships the objects enumeratedin the introduction. namely a distortion free. simple. economical andefficient system for reproduction and enlargement processes over a verywide range of magnification. are obtainable. Uniform light distributionover the whole image format is obtained.

The following 1 to IV tables give four examples of a 174.5 reproductionobjective with design parameters calculated for a focal lengthf=100 mm.Each of the examples are particularly suitable for the degree ofmagnification given in the example. but are also suitable with a rangeabove and below the given degree of magnification by variance of thegiven parameters, as indicated later.

From the foregoing table it may be calculated that jl, 97.68

107.62 j}- 163.06 f 36.83 j}; 96.80

Example 11:

B 14.8 x R 44.355 n,, R- .=+ll3.48 d =6.84 1.70154 41.1 R, 29.72 m 0.33air R =+97.06 t.1- -=8.15 1.70154 41.1 d 3.42 1.76182 26.5

m. 19.22 air air R 22.03 11,-, 9.12 1.65844 50.8 R 22.13 m. 0.65 air R37.41 1.1,. 5.54 1.62536 35.6

whereby f, 99.73 f 110.65 f.- 158.13 f 37.58 1;, 100.68

- Example 111:

B 21 x 1 n,, v R. 110.7 d =7.9 1.70154 41.1

-Continued Example 111:

R 29.25 l'n 0.22 air R,=+91.2-1 t1. .=x.33 1.70154 41.1 R; 18.97 1.1;,3.51 1.76 I 82 26.5 R.- 20.43 m 19.08 air R =-27.68 d,=2.41 1.57501 41.3R 169.08 1n; 0.22 air R 21.05 d 9.43 1.65844 50.8

, m 0.44 air whereby Example 1V:

B 29.7 R 44.55 n,, v R =+113.99 d,=7.99 1.70154 41.1 R 29.96 m 0.61 air'R.=+97.91 d. ,=8.18 1.70154 41.1 R; d 3.44 1.76182 26.5 R m 19.25 aird, 2.58 1.57501 41.3 R, m 0.61 air R (1;, 9.84 1.65844 50.8 R m 0.68 airR d 5.53 1.62536 35.6

whereby:

In the foregoing examples the conventional measurements are inmillimeters.

The radii of curvature R R R R R... R 11 y be changed within :t 10percent. R R within i 20 percent and R. R within 5 percent. The axialthick- .nesses d, and 11.; may be changed within i 20 percent and d (1 dwithin percent. The airspaces m m 111 may be changed within 30 percentand m within 10 percent. The refracting indices 11., n,, n,, n,, may bechanged within 20 percent and n, and n,, within 1 10 percent.

In the foregoing examples R R are the radii of curvature of theindividual refracting surfaces. d, 11.; are the axial thicknesses of theindividual components. m through 111 are the thicknesses of theairspaces between the individual components. 11,, is the refractingindex for the D-line of the spectrum and v is the Abbe number. Themeasurements are all taken in millimeters.

Due to the advantageous state of correction and the practical totalremoval of all vignetting and image distortion. the above describedoptical system of a reproduction objective exemplified in the fourexamples and varied within the defined ranges is suitable for ad vancedreproduction and enlargement particularly in the image magnificationrange of anywhere between 7 X to 30 X.

Modification of the Examples by the variances indi cated above willproduce lens objectives having the distinct advantages and benefitsenumerated earlier. Such systems as noted adaptable to speeds as high asf/4.5

within the broad magnification range of 7 30X with very littlevignetting or distortion. In view of this the present disclosure isillustrative only of the invention and may be modified as desired withinthe scope of the claims.

What is claimed is:

1. An objective lens system comprising five optical components separatedby airspaces wherein the first optical component. placed next to theimage plane. is a positive meniscus. the second optical componentadjacent to it is a negative meniscus composed of two cemented elements.both said first and second components representing the front portion ofthe objective. the third. fourth and fifth components comprise the rearportion of the objective and consist of three menisci the two extremeones having a negative refractivity. the middle one having a positiverefractivity, said front and rear portions being separated by a largespace in which a mechanical diaphragm is located, and wherein the designparameters conform substantially R, 43.87 11,, u R .=+1l4.82 d =6.|51.70154 41.1 R; 29.93 n1 0.18 air R,=+)2.51 (1 14.45 1.70154 41.1 R;,=+19,15 d 3.40 1.76182 26.5 R 209 m 19.25 air 1 28.06 d 2.48 1.57501 41.3R,.= 144.2 m =0.18 air R 21.29 11 9.28 1.65844 50.8 I 21.39 m. 0.37 airR.,= 36.63 d 5.97 1.612536 35.61

wherein .11; 96.80 where R R are the radii of curvature of individualrefracting surfaces;

:1, 11.; are the axial thicknesses of individual elements;

n1 171 are axial airspaces between individual optical components;

71,, is the refractive index for the spectral D-line;

v is the Abbe number and f. f,,.f, .f,,,f,; are the focal lengths ofindividual optical components.

2. An objective lens system comprising five optical components separatedby airspaces wherein the first optical component. placed next to theimage plane, is a positive meniscus. the second optical component ad-'jacent to it is a negative meniscus composed of two cemented elements.both said first and second components representing the front portion ofthe objective, the third. fourth and fifth components comprise the rearportion of the objective and consist of three menisci the two extremeones having a negative refractivity. the middle one having a positiverefractivity. said front and rear portions being separated by a largespace in which a mechanical diaphragm is located. and wherein the designparameters conform substantially R 44.355 11,, v R- =+113.4S 1.1,=6.1-'41.70154 41.1 R 29.72 111 00 3 air R. 97.06 2 1.70154 41.1 R 19.281.76182 26.5 R 20.75 air R 28.12 157501 41.3 R 167.85 m 0.33 air R 22.03d 9.12 165844 50.8 R 22.13 m. 0.65 air R 37.41 t1 5.54 1.612536 35.6

where j}; 100.68 where R R are the rad-ii of curvature of individualrefracting surfaces; d (1,; are the axial thicknesses of individualelements; m "1 are the axial airspaces between individual opticalcomponents 11,, is the refractive-index for the spectral D-line; 1/ isthe Abbe 11111111561 and l j:,.f,,. /}-.f,,.f,; are 'the'focal lengthsof individual components.

3. An objective "lens system comprising five optical componentsseparated by airspaces wherein the first optical component. placed nextto the image plane. is a positive meniscus the second optical componentadjacent to it is a negative meniscus composed of two cemented elements.both said first and second components representing the front portion ofthe objective. the third. fourth and fifth components comprise the rearportion of the objective and consist of three menisci the two extremeones having a negative refractivity. the middle one having a positiverefractivity. said front and rear portions being separated by a largespace in which a mechanical diaphragm is located. and wherein the designparameters conform substantially to:

n, u R. ,=+110.7 1.70154 41.1 R. 29.25 air 1=+91.24 1.70154 41.1 R,-,18.97 1.76182 26.5

air

1.57501 41.3 air 6 21.05 1.65844 511.8 111 1111' R,.= 36.48 d..=4.6i1.62536 35.6

where f, 104.1 1 f 1 12.22 f,- 154.39 35.61 f 91.45 where R R are theradii of curvature of individual refracting surfaces;

d (1.; are the axial thicknesses of individual elements;

in m. are the axial airspaces between individual optical components;

11,, is the refractive index for the spectral Dline:

v is the Abbe number and j' .f,,.f,-, j}; are the focal lengths ofindividual opti cal components.

4. An objective lens system comprising five optical components separatedby airspaces wherein the first optical component. placed next to theimage plane. is a positive meniscus, the second optical componentadjacent to it is a negative meniscus composed of two cemented elements,both said first and second components representing the front portion ofthe objective, the third fourth and fifth components comprise the rearportion of the objective and consist of three menisci the two extremeones having a negative refractivity. the middle one having a positiverefractivity. said front and rear portions being separated by a largespace in which a mechanical diaphragm is located. and wherein the designparameters conform substantially to:

R, R are the radii of curvature of individual refracting surfaces;

:1, (1 are the axial thicknesses of individual elements;

m, 111 are the axial airspaces between individual optical components;

11,, is the refractive index for the spectral D-line;

: is the Abbe number and f, f,,,j}- j},.j} are the focal lengths ofindividual opti-

1. An objective lens system comprising five optical components separatedby airspaces wherein the first optical component, placed next to theimage plane, is a positive meniscus, the second optical componentadjacent to it is a negative meniscus composed of two cemented elements,both said first and second components representing the front portion ofthe objective, the third, fourth and fifth components comprise the rearportion of the objective and consist of three menisci the two extremeones having a negative refractivity, the middle one having a positiverefractivity, said front and rear portions being separated by a largespace in which a mechanical diaphragm is located, and wherein the designparameters conform substantially to:
 2. An objective lens systemcomprising five optical components separated by airspaces wherein thefirst optical component, placed next to the image plane, is a positivemeniscus, the second optical component adjacent to it is a negativemeniscus composed of two cemented elements, both said first and secondcomponents representing the front portion of the objective, the third,fourth and fifth components comprise the rear portion of the objectiveand consist of three menisci the two extreme ones having a negativerefractivity, the middle one having a positive refractivity, said frontand rear portions being separated by a large space in which a mechanicaldiaphragm is located, and wherein the design parameters conformsubstantially to:
 3. An objective lens system comprising five opticalcomponents separated by airspaces wherein the first optical component,placed next to the image plane, is a positive meniscus, the secondoptical component adjacent to it is a negative meniscus composed of twocemented elements, both said first and second components representingthe front portion of the objective, the third, fourth and fifthcomponents comprise the rear portion of the objective and consist ofthree menisci the two extreme ones having a negative refractivity, themiddle one having a positive refractivity, said front and rear portionsbeing separated by a large space in which a mechanical diaphragm islocated, and wherein the design parameters conform substantially to: 4.An objective lens system comprising five optical components separated byairspaces wherein the first optical component, placed next to the imageplane, is a positive meniscus, the second optical component adjacent toit is a negative meniscus composed of two cemented elements, both saidfirst and second components representing the front portion of theobjective, the third, fourth and fifth components comprise the rearportion of the objective and consist of three menisci the two extremeones having a negative refractivity, the middle one having a positiverefractivity, said front and rear portions being separated by a largespace in which a mechanical diaphragm is located, and wherein the designparameters conform substantially to: